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41.
Peritoneal washings are routinely performed in the staging evaluation of carcinomas of the ovary and in "second-look" explorations; major problems in the evaluation of these specimens continue to be the distinction between atypical mesothelium and adenocarcinoma and the identification in an otherwise inflammatory specimen of rare cells of adenocarcinoma, which may be undetected by the most trained individual. Monoclonal antibody (MAb) B72.3, reactive with an oncofetal, tumor-associated glycoprotein (termed TAG-72; MW greater than 1000 kd) expressed in a variety of epithelial malignancies but not generally expressed in benign or malignant mesothelium, was reacted with sections from the paraffin-embedded cell blocks of 185 peritoneal washings from 180 patients with extant cancer or a prior history of malignancy. One hundred four of the washings were initially interpreted as atypical mesothelium, with no evidence of malignancy; when reacted with MAb B72.3, 6 of these specimens demonstrated groups of metastatic adenocarcinoma cells not appreciated by the usual cytologic criteria. Of the 81 washings interpreted as showing cells of adenocarcinoma, 73 demonstrated expression of TAG-72 from both gynecologic and nongynecologic malignancies. In the remaining 49 cases without an associated malignant process, MAb B72.3 did not stain atypical mesothelium, but did react, however, with benign endometrial cells and müllerian inclusions in two cases. MAb B72.3 may be used as a diagnostic adjunct to the routine cytologic evaluation of malignancy in peritoneal washings; reactivity with MAb B72.3 may indicate the need for further evaluation to define the presence of a malignancy or an advanced cancer.  相似文献   
42.
43.

Background

Primary care staffing decisions are often made unsystematically, potentially leading to increased costs, dissatisfaction, turnover, and reduced quality of care. This article aims to (1) catalogue the domain of primary care tasks, (2) explore the complexity associated with these tasks, and (3) examine how tasks performed by different job titles differ in function and complexity, using Functional Job Analysis to develop a new tool for making evidence-based staffing decisions.

Methods

Seventy-seven primary care personnel from six US Department of Veterans Affairs (VA) Medical Centers, representing six job titles, participated in two-day focus groups to generate 243 unique task statements describing the content of VA primary care. Certified job analysts rated tasks on ten dimensions representing task complexity, skills, autonomy, and error consequence. Two hundred and twenty-four primary care personnel from the same clinics then completed a survey indicating whether they performed each task. Tasks were catalogued using an adaptation of an existing classification scheme; complexity differences were tested via analysis of variance.

Results

Objective one : Task statements were categorized into four functions: service delivery (65%), administrative duties (15%), logistic support (9%), and workforce management (11%). Objective two : Consistent with expectations, 80% of tasks received ratings at or below the mid-scale value on all ten scales. Objective three : Service delivery and workforce management tasks received higher ratings on eight of ten scales (multiple functional complexity dimensions, autonomy, human error consequence) than administrative and logistic support tasks. Similarly, tasks performed by more highly trained job titles received higher ratings on six of ten scales than tasks performed by lower trained job titles. Contrary to expectations, the distribution of tasks across functions did not significantly vary by job title.

Conclusion

Primary care personnel are not being utilized to the extent of their training; most personnel perform many tasks that could reasonably be performed by personnel with less training. Primary care clinics should use evidence-based information to optimize job-person fit, adjusting clinic staff mix and allocation of work across staff to enhance efficiency and effectiveness.  相似文献   
44.

Background  

Adverse drug reactions (ADRs) are now recognized as an important cause of hospital admissions, with a proportion ranging from 0.9–7.9%. They also constitute a significant economic burden. We thus aimed at determining the prevalence and the economic burden of ADRs presenting to Medical Emergency Department (ED) of a tertiary referral center in India  相似文献   
45.
P2RX7 is an ATP-gated ion channel, which can also exhibit an open state with a considerably wider permeation. However, the functional significance of the movement of molecules through the large pore (LP) and the intracellular signaling events involved are not known. Here, analyzing the consequences of P2RX7 activation in primary myoblasts and myotubes from the Dmdmdx mouse model of Duchenne muscular dystrophy, we found ATP-induced P2RX7-dependent autophagic flux, leading to CASP3-CASP7-independent cell death. P2RX7-evoked autophagy was triggered by LP formation but not Ca2+ influx or MAPK1-MAPK3 phosphorylation, 2 canonical P2RX7-evoked signals. Phosphoproteomics, protein expression inference and signaling pathway prediction analysis of P2RX7 signaling mediators pointed to HSPA2 and HSP90 proteins. Indeed, specific HSP90 inhibitors prevented LP formation, LC3-II accumulation, and cell death in myoblasts and myotubes but not in macrophages. Pharmacological blockade or genetic ablation of p2rx7 also proved protective against ATP-induced death of muscle cells, as did inhibition of autophagy with 3-MA. The functional significance of the P2RX7 LP is one of the great unknowns of purinergic signaling. Our data demonstrate a novel outcome—autophagy—and show that molecules entering through the LP can be targeted to phagophores. Moreover, we show that in muscles but not in macrophages, autophagy is needed for the formation of this LP. Given that P2RX7-dependent LP and HSP90 are critically interacting in the ATP-evoked autophagic death of dystrophic muscles, treatments targeting this axis could be of therapeutic benefit in this debilitating and incurable form of muscular dystrophy.  相似文献   
46.

Background and Aims

Silene dioica and S. latifolia experience only limited introgression despite overlapping flowering phenologies, geographical distributions, and some pollinator sharing. Conspecific pollen precedence and other reproductive barriers operating between pollination and seed germination may limit hybridization. This study investigates whether barriers at this stage contribute to reproductive isolation between these species and, if so, which mechanisms are responsible.

Methods

Pollen-tube lengths for pollen of both species in styles of both species were compared. Additionally, both species were pollinated with majority S. latifolia and majority S. dioica pollen mixes; then seed set, seed germination rates and hybridity of the resulting seedlings were determined using species-specific molecular markers.

Key Results

The longest pollen tubes were significantly longer for conspecific than heterospecific pollen in both species, indicating conspecific pollen precedence. Seed set but not seed germination was lower for flowers pollinated with pure heterospecific versus pure conspecific pollen. Mixed-species pollinations resulted in disproportionately high representation of nonhybrid offspring for pollinations of S. latifolia but not S. dioica flowers.

Conclusions

The finding of conspecific pollen precedence for pollen-tube growth but not seed siring in S. dioica flowers may be explained by variation in pollen-tube growth rates, either at different locations in the style or between leading and trailing pollen tubes. Additionally, this study finds a barrier to hybridization operating between pollination and seed germination against S. dioica but not S. latifolia pollen. The results are consistent with the underlying cause of this barrier being attrition of S. dioica pollen tubes or reduced success of heterospecifically fertilized ovules, rather than time-variant mechanisms. Post-pollination, pre-germination barriers to hybridization thus play a partial role in limiting introgression between these species.  相似文献   
47.
Escherichia coli asparagine synthetase B (AS-B) catalyzes the formation of asparagine from aspartate in an ATP-dependent reaction for which glutamine is the in vivo nitrogen source. In an effort to reconcile several different kinetic models that have been proposed for glutamine-dependent asparagine synthetases, we have used numerical methods to investigate the kinetic mechanism of AS-B. Our simulations demonstrate that literature proposals cannot reproduce the glutamine dependence of the glutamate/asparagine stoichiometry observed for AS-B, and we have therefore developed a new kinetic model that describes the behavior of AS-B more completely. The key difference between this new model and the literature proposals is the inclusion of an E.ATP.Asp.Gln quaternary complex that can either proceed to form asparagine or release ammonia through nonproductive glutamine hydrolysis. The implication of this model is that the two active sites in AS-B become coordinated only after formation of a beta-aspartyl-AMP intermediate in the synthetase site of the enzyme. The coupling of glutaminase and synthetase activities in AS is therefore different from that observed in all other well-characterized glutamine-dependent amidotransferases.  相似文献   
48.
A significant number of nonmalignant, progressive childhood disorders respond to bone marrow transplantation (BMT). Toxic myeloablative pretreatment regimens, graft failure, and graft-vs-host disease complicate the utility of BMT for neonatal treatment. We recently demonstrated high-dose BMT in neonatal animals enables chimeric engraftment without toxic myeloablation. Reagents that block T cell costimulation (anti-CD40L mAb and/or CTLA-4Ig) establish tolerant allogeneic engraftment in adult recipients. Donor lymphocyte infusion (DLI) re-establishes failing grafts and treats malignant relapse via a graft-vs-leukemia response. In this study, we tested the hypothesis that combining these approaches would allow tolerant allogeneic engraftment devoid of myeloablation in neonatal normal and mutant mice with lysosomal storage disease. Tolerant chimeric allogeneic engraftment was achieved before DLI only in the presence of both anti-CD40L mAb and CTLA-4Ig. DLI amplified allografts to full donor engraftment long-term. DLI-treated mice either maintained long-term tolerance or developed late-onset chronic graft-vs-host disease. This combinatorial approach provides a nontoxic method to establish tolerant allogeneic engraftment for treatment of progressive childhood diseases.  相似文献   
49.
Binding of biologically active 3H-PGE2 to particulate fractions of porcine gastrointestinal mucosa and muscle was investigated. Specific binding activity was detected in the 2500 xg and 30,000 xg sedimentation fractions of mucosa from esophagus, fundus, antrum, duodenum, ileum and colon, as well as in serosal muscle taken from the antrum, ileum, and colon. Optimal binding (> 40 fmol/mg protein) was observed in the 30,000 xg fraction of fundic mucosa incubated at pH 5.0. The characteristics of 3H-PGE2 binding were variable in the remainder of the gastrointestinal tract although binding in these tissues was significantly less (0.2 to 15 fmol/mg protein) than that observed in the fundic mucosa. These data suggest that the cellular and/or subcellular site of PG binding is not uniform throughout the gastrointestinal tract. In fundic mucosa removal of the surface epithelial layer by scraping did not significantly alter the total binding activity for PGE. This result suggests that in gastric secretory mucosa optimal binding activity for PGE2 occurs within the gastric pits deep to the surface epithelium.  相似文献   
50.
The viability of Bacillus megaterium spores has been determined after exposure to vacuum dehydration at temperatures between 0 and 65 °C, for periods up to 24 hr. A curvilinear relationship has been demonstrated between viability and drying temperature, with minimum viability occuring around 15 °C and increases in viability being shown above 35 °C. In contrast to vegetative bacteria, reequilibration of the dried spores to 2 × 10?3 or 10 Torr aqueous vapor pressure, and/or subsequent exposure to oxygen had no effect on viability. Dehydration, rehydration and oxygen treatments had no effect on the time for outgrowth of the spores or on the growth rate of the resultant vegetative cells. Physical loss of spores from samples was not demonstrated during any of these treatments. Evidence has been presented for a novel type of spore activation, which occurs during vacuum dehydration at high temperatures, to an extent that is dependent upon drying time. The mechanism of this activation is unlike that of conventional heat or chemical activation but is oxygen independent and unaffected by reequilibration to 2 × 10?3 or 10 Torr.  相似文献   
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